37. Structure and evolution of meteor streams

Abstract

Our present knowledge of meteor streams is based on three types of meteor showers: (1)About one or two dozen major showers that recur annually in optical and radar records of meteor activity.(2)An indefinite number of minor showers, hardly distinguishable from the sporadic background, which can be traced only by comparing individual meteor orbits.(3)Rare appearances of temporary showers, sometimes producing extraordinary meteor displays. These include prominent concentrations of meteors within some of the annual streams, meeting the Earth under specific conditions.